The present invention relates to a printer device such as a laser printer or a copying machine which prints or copies characters or figures. More specifically, the present invention relates to a printer device which can erase recorded items printed or copied on a medium (hereinafter referred to as "paper") such as a paper so that the paper can be reused.
In the present specification, a printer device means a printing machine or a copying machine which can print, transfer or copy characters and figures by using ink, toner or the like. For example, a laser printer, a copying machine and the like are included.
According to a conventional laser printer or a copying machine, ink or toner made of, for example, carbon is adhered or burned to a paper surface so as to record characters or figures. Such ink or toner is made of a material which is chemically stable and does not fade in color, so that the recorded characters or figures do not semipermanently disappear.
Thus, although the conventional printing method is convenient for the long preservation of documents, it has a problem that once printed paper can not be reused.
With the recent rapid increase of an information amount and development of OA machines such as a personal computer and a word processer, opportunities of copying or printing (hereinafter referred to as simply "printing") information are greatly increased. Further, the amount of printed matter which is used only for a short time after printing, is increasing more and more. That is, in a case where an original of information exists in the printed matter or an OA machine, and when a user reads the information at a place separated from a terminal device, the information is outputted from the OA machine to form the printed matter. However, when the copied matter is once used, it often becomes useless. Further, since the original of information stored in the OA machine is often renewed, the lifetime of the printed matter as the copy of the original is very short. Conventionally, in such a case, the printed matter is thrown away after at most, the rear surface of the paper is used. Accordingly, there arise problems that the amount of dust remarkably increases and the paper is wasted, which leads to the destruction of global environment such as forest resources.